Question:
Mark (✓) against the correct answer
$\left(\frac{-5}{4}\right)^{-1}=?$
(a) $\frac{4}{5}$
(b) $\frac{-4}{5}$
(C) $\frac{5}{4}$
(d) $\frac{3}{5}$
Solution:
(b) $\frac{-4}{5}$
We ahve:
$\left(\frac{-5}{4}\right)^{-1}$
$=\frac{1}{\left(\frac{-5}{4}\right)}$
$=1 \times \frac{4}{-5}$
$=\frac{4}{-5}$
$=\frac{4 \times-1}{-5 \times-1}$
$=\frac{-4}{5}$